1. Field of the Invention
The present invention relates, in general, to hand-operated control levers for engaging and disengaging an apparatus, and in particular, to a hand-operated control lever that engages and releases a linkage when operated in a first direction, but that becomes disjointed to prevent breakage when forced to move in other directions.
2. Description of Related Art
Hand-operated control lever mechanisms are well-known known for use on vehicles such as motorcycles, bicycles, all-terrain vehicles, and the like, so as to operate a clutch or a brake, etc. However, prior art levers are prone to breakage in the event of an accident or when the vehicle falls over, and the broken lever can seriously maim the rider when broken metal edges lacerate the riders hands, limbs, and torso.
It is therefore desirable to have an improved control lever that allows normal operation when moved in a first direction by the operator's grip, but that releases without breaking when moved in other directions. It is further desirable that the control lever naturally return to its normal mode of operation when the abnormal stressing forces of an accident or fall are removed from the lever. It is still further desirable that the control lever not engage its linkage mechanism when moved in directions other than the normal direction of operation.
A preliminary patentability search in Class 74, Subclasses 23, 502.2, 501.6 and 489, and also using text searching on the Patent and Trademark Office EAST database system, produced the following patents, some of which may be relevant to the present invention: Ross-Myring, U.S. Pat. No. 4,088,040 (issued May 9, 1978); Lee, U.S. Pat. No. 5,954,161 (issued Sep. 21, 1999); Shirayanagi, U.S. Pat. No. 6,393,933 (issued May 28, 2002); and Brainard, U.S. Pat. No. 6,516,682 (issued Feb. 11, 2003).
The inventor is also aware of the following prior art: Dawson, U.S. Pat. No. 4,726,252 (issued Feb. 23, 1988); Hornady, U.S. Pat. No. 4,730,509 (issued Mar. 15, 1988); Warren et al., U.S. Pat. No. 6,047,611 (issued Apr. 11, 2000); and Barnett, U.S. Pat. No. 6,393,936 (issued May 28, 2002).
Ross-Myring, U.S. Pat. No. 4,088,040 (issued May 9, 1978), discloses a control lever that disjointingly pivots about a circumferential surfaces of a circular pivot ring (see FIGS. 2–7). The handle pivots in all directions and is retained to its mounting by the actuating cable. A disadvantage of the lever disclosed in the Ross-Myrig is that it actuates the cable operated by the lever when the lever is pivoted in any direction.
Lee, U.S. Pat. No. 5,954,161 (issued Sep. 21, 1999), discloses a control lever that pivots in a single plane about an arcuate surface, but the lever does not allow sidewardly disjointed pivoting.
Shirayanagi, U.S. Pat. No. 6,393,933 (issued May 28, 2002), discloses a control lever that pivots sidewardly and in and out, but the pivoting is about fixed axles without becoming disjointed.
Brainard, U.S. Pat. No. 6,516,682 (issued Feb. 11, 2003), discloses a pivoting lever but, like older levers, pivots about an axle pin in a single plane rather than becoming disjointed.
Dawson, U.S. Pat. No. 4,726,252 (issued Feb. 23, 1988), discloses a lever arm that pivots about dual axle pins but does not become disjointed.
Hornady, U.S. Pat. No. 4,730,509 (issued Mar. 15, 1988), discloses a break-away control lever that is pivoted on a two-pronged fork about fixed axle pivot pins and becomes dislocated when forced out of its direction of normal motion.
Warren et al., U.S. Pat. No. 6,047,611 (issued Apr. 11, 2000), discloses multi-pivoted lever that pivots in multiple planes. However, like other references, it pivots about a plurality of fixed pivot axle pins.
Barnett, U.S. Pat. No. 6,393,936 (issued May 28, 2002), discloses a handle that pivots about a fixed pivot pin axle in one plane.
Additionally, the inventor is aware of some advertisements for so-called “unbreakable” clutch levers from searching the internet: “Bob's Cycle & Smowmobile Supply Lever ASV Clutch Hydric [sic],” found on the internet at www.cpostores.com/bobscyle/browse.cfm/4,44724,1,39,2310.html (date unknown), and “ASV Inventions Clutch Level,” found on the internet at www.motoworldracng.com/asv_lever.html (date unknown), both disclose a pivoting lever that pivots outward. The lever pivots about a fixed pivot pin in one plane only and not side-to-side. Another advertisement, “Arcx Folding Lever—Just Like Sebastian Uses,” found on the internet at www.arclevers.com/tests/arclevers.html (April and May, 2000), discloses a double-jointed lever that can pivot outwardly but not sidewardly, and does not appear to disjoint about an arcuate fulcrum surface.
None of these references, either singly or in combination, disclose or suggest the present invention.